Midnight Building is a single-player casual and arcade game in which players navigate a dark labyrinth, starting from the eighth floor and descending to the first. In this game, players begin each round with a brief glimpse of the labyrinth, allowing them to locate keys and the vault before the darkness fully engulfs the maze, leaving only the immediate surroundings illuminated. It stands out with its tense gameplay that combines exploration, stealth, and quick decision-making, as players must collect keys, unlock the vault, and return to the center of the maze to progress to the next floor, all while avoiding hostile green men.